Solid carbon dioxide converter



Jan. 16, 1934. J. c, GoosMANN soun CARBON nroxm coNvEnTER Filed April 15,-1931 l n f2s.. A Lawwrl INVENTOR 4:JLajxaw G- Goosrnann BY hisATTori'lxusYesl PM Patented Jan. 16, 1934 UNITED STATES 1,943,320 y sOLm CARBON mOxmE CONVERTER Justus C. Goosmann, Mount Vernon, vN. Y., as-

sgnor to American Dryice Corporation, New York, N. Y., a corporation of New York Application April .15, 1931'. Serial No. 530,202

17 Claims. (Cl. 62-91.5)

This invention relates in general to apparatus Irigerating, carbonating and other purposes.

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One of the objects of this invention is the provision of a converter in which solid carbon dioxide is converted into liquid carbon dioxide.

A further object of this invention is the provision in connection with the above. converter of a liquid receiver.

A still further object of this invention is the provision with such a converter and receiver of a carbonator in which the liquid to be carbonated is cooled with liquid carbon dioxide and then carbonated with carbon dioxide gas.

An important object of this invention resides in the employment of a heat exchanger in the liquid line to the cooling coil of the carbonator for the rellquefaction of any gaseous carbon dioxide present in the line.

A still further Object is the provision with apparatus of this nature of a gas receiver in which the carbon dioxide gas is accumulated after use for further use.

An important object of this invention is the provision of connections between the converter and receiver so that after the converter is re charged with solid carbon dioxide, the gas pressure may be built up therein to thepoint where .the solid may be converted to liquid form with little loss in time after such re-charging operation.

'I'hese and other objects as will appear from the following disclosure are secured by means of this invention.

This invention resides substantially in the combination, construction, arrangement and relative location of parts all as will be described in greater detail hereinafter.

Referring to the drawing- Figure l is a'diagrammatic view of the apparatus of this invention showing the converter in cross section.

This invention will be best understood by direct and detail reference to the structure disclosed in the drawing and a description of the voperation thereof. The converter comprises a tank 1 of suitable shape and strong enough to withstand the pressures involved. The tank is closed at the bottom end by means of a wall 7 which forms an airtight seal therewith and may be secured in place by welding, for example, the tank is supported by means of legs or standardslO of suitable construction. At the top of the tank is a movable cover 2 which fits snugly within the tank and lies under the internally extending flange as shown. A suitable sealing ring6 is interposed between the cover or closure 2 and the annular rim of the tank. The closure is securely heldin place by means of a transverse yoke or bar 3 which rests at its ends on the upper end of the tank. A bolt 4 interconnects the closure with the yoke and a suitable nut 5 is provided for drawing the closure tightlyup against the sealing ring. This construction is somewhat similar to the manhole cover of a steam boiler and it will be noted that the pressure within the container acting upwardly on the closure also firmly forces it against its seat. At 7' is shown a suitable pressure gauge for indicating the pressure within the tank. Supported on the bottom wall and within the tank is a condenser coil 8 which is open at its upper end as indicated by the short pipe extension 9 to the interior of the container. The lower end of the condensercoil is provided with a pipe extension 11 which extends exteriorly of the casing. Of course, the opening through which the pipe extension l1 passes may be hermetically sealed by welding the extension 11 to the wall '7.

The extension 11 is connected by pipe 12 through a valve '13 into the liquid receiver tank 14. A valve control pipe extension 15 is connected to the bottom of the tank so that dirt, moisture and other materials may be blown out fromthe bottom y of the tank therethrough. Pipe 16 connects the top of the liquid receiver 14 through a control valve 1'7 to the top of tank 1 through a similar'control valve 18 as shown. Pipe 16 is effectively extended down into tank 14 near the bottom thereof by means of extension 17a. The pipe 16 which connects intotank 1 is provided with a. safety blow out disc 19 in accordance with well known practice so that il the pressure in the tank exceeds 'a predetermined value the safety disc will be disrupted to release the pressure in the tank.

The liquid cooler and carbonator has been shown diagrammatically at 20. The carbonator has only been shown diagrammatically since any known form of carbonator may be used in connection with the apparatus of this invention. Pipe 16 is connected to the carbonating chamber by means of a pipe 21 in which pipe is provided a pressure reducer valve 22. The pressure reducer valve 22 may likewise be of any well known form and is of a construction which effects the reduction in pressure of the liquid as it passes therethrough. Such valves are yadjustable so as to control the ratio of pressure on each side of the valve.

Pipe 21 delivers into the carbonating chamber where the carbon dioxide gas is intimately mixed with the liquid to be carbonated. This liquid may be cooled by means of the cooling coil- Pipe 21 is connected to the gas holder by means 120 of pipe 23 through a control valve 24. The gas holder is provided with a suitable pressure gauge.

As shown a heat exchanger may be employed in the liquid line 26. This heat exchanger comprises a cooling coil 35 connected directly in line 26. Line 26 is provided with an expander or a pressure reducing valve 27'. A closed casing 34 encloses the cooling coil 35. Line 26 between the earbonator and the expander valve 27 is connected to the casing 34, through pipe line 39 and expander valve 38. 'Ihe casing 34 is also connected to pipe line 23 by the pipe connection 36. The carbonator 20 is provided with a gas discharge line 32 and the blow-orf valve 33.

In the operation of this apparatus tank 1 is charged with a suitable amount of solid carbon dioxide preferably in the form of blocks or lumps. The cover is put in place and tightly pressed against its seat. If there is liquid carbon dioxide in the receiver 14, valves 17 and 18 are 'opened with valve 22 closed and suf@- cient of the liquid may be discharged through pipe 16 into the top of tank l to build up a gas pressure therein to the desired degree by the :dashing of the liquid into gas as it enters the tank. As the solid. carbon dioxide in the tank 1 sublimates, that is passes directly in the gaseous form, it will be forced into the condenser coils 8 through the open end 9. The very cold gas thus circulating through the condenser coils in heat exchange relation with the solid carbon dioxide surrounding the coils is condensed therein and is delivered into the tank 14 through pipes 1l and 12 and valve 13 which will be opened when the pressure in tank 1 is substantially equal to the pressure in tank 14. Thus, as the solid carbon dioxide sublimates the gas formed will be condensed into the liquid phase and accumulated in the receiver 14.

The pressure in tank 1 may be of the order of 800 pounds per square inch which is given by way of example rather' than in any limiting.

sense. The liquid from the receiver 14 is deiivered into pipe 26 through the pressure reducing valve 27 which may be set to effect a pressure drop to about 150 pounds per square inch.

The carbon dioxide thus delivered into pipe 26- circulates through the cooling coil 28 to cool the liquid in the carbonator. Carbon dioxide in gaseous form is then delivered to the gas holder 25, valve 30 being open. With valve 18 closed and valve 1'? open, liquid from receiver 14 will be delivered to pipe 21 through the pressure reducing valve 22. This valve may be set to deliver carbon dioxide gas into pipe 21 at a suitable carbonating pressure such as 30 pounds per square inch. This gas when delivered into the carbonator is employed to impregnate the liquid to be carbonated. With this arrangement the carbonator works very effectively because the liquid to be carbonated is reduced to a low temperature at a given pressure of the carbonating gas. A liquid carbonates more easily the lower its temperature. Pipe connection 23 and control valve 24 are provided so that during the periods of inoperativeness of the converter carbonating action can be continued by delivering gas from the gas holder to pipe 21 through pipe 23.

It is well known and has long been observed that carbon dioxide in process of liquefaction behaves diilerently than other well known gases such as for example ammonia. Ammonia during its process of liquefaction cannot be cooled to a lower temperature than that of the water overflow from the cooling condenser, whereas carbon dioxide on the other hand may be subcooled below the overflow temperature of the water. It has been observed in many tests that the temperature of carbon dioxide gas in a condenser during condensation varies considerably and this variation can be traced to the point of change in state, that is, where the gas changes 'into a liquid. This is due in a considerable measure to the fact that heat does not readily travel through a layer of carbon dioxide gas or vapor. The insulating property of this gas is high, in fact, much higher than that of air so that the temperature of theliquid at the end of condensation, and where this temperature is lowest, is not aiected by the higher temperature of the gas within the condenser, although the gas as Well as the liquid, is at the same pressure.

This condition becomes more drastic and more apparent and is easily observed when solid carbon dioxide sublimes in a pressure vessel. In this case there appears to be an entire disruption of the relationship between temperature and pressure. For instance, the solid carbon dioxide at the bottom of the container is little influenced by the pressure present in the same container. The temperature of the solid carbon dioxide deviates little from its temperature of 109 F. regardless of the pressure which develops in the container by the sublimation of the solid into gas. The temperature of the liquid must necessarily be regulated above the temperature of crystallization which is adjusted by the flow of liquid out of the container into the liquid receiver. It is necessarily true that if the liquid which has collected at the bottom of the container is allowed to remain there in a static condition, it will be cooled by the solid carbon dioxide to the point of crystallization and thus solidified.

However, when this liquid is drawn from the container at a temperature above crystallization, it will not freeze as will readily be apparent. The pressure on the other hand which is developed by the continuous sublimation of the enclosed solid carbon dioxide mounts steadily to higher levels. Therefore, temperatures at great variation can be observed in the container; for instance, the gas which collects near the top of the container may approach the temperature existing on the outside thereof. At the approximate mid-distance between the top and the bottom of the container, the temperature will be found considerably lower; at the bottom temperatures where the liquid exists, temperatures of 40 F. occur, and, at the same time, the temperature of the metal bottom of the container upon which the solid carbon dioxide rests will be as low as 100 F. During all of this time, the pressure in the container will be close to that corresponding with the temperature of the gas near the top. In other words, if the temperature of the gas near the top of the container is approximately 60 F., the pressure within the container would be found to be above 700 pounds per square inch. Here again, it seems apparent that the insulating property of the gas prevents even temperature equalization of the gaseous body within the container.

Experiments carried on by competent physicists have shown that. the volume of solid carbon ing; while carbon dioxide decreases in volume while freezing and increases in volume when melting. This increase is as much as 28.5% at the triple point, but decreaseswith rising pressure.

The temperature increase at least in the solid field is, therefore, 1 F. per 1,544 pounds pressure. Tammann and Bridgeman found that the sublimation of solid carbon dioxide can be prevented only at an enormous pressure. For in-v stance, solid carbon dioxide which has a pressure at the triple point of 15.14 pounds per square inch absolute and a corresponding temperature of 69.86 F. requires an increase in this pressure to 14,220 pounds per square inch with a rise in its temperature to 35.14 F. This demonstrates that the sublimation of solid carbon dioxide can be prevented only at an enormous increase in pressure.

This explains the increase in pressure within the container during the sublimation of solid carbon dioxide to above 700 pounds per square inch when enclosed in a pressure vessel, while the liquid temperature near the bottom maybe as low as -40 F. with a still much lower tem-s perature at the bottom where solid carbon dioxide is in. direct contact with the metal of the container.

The equilibrium condition for the fluid phases Aof solid carbon dioxide shows that the pressure in the container would still climb much higher if none of the enclosed carbon dioxide is withdrawn. Hence, in practice, the apparatusis provided with a safety disc proportioned to break at 1200 pounds per square inch, so that the container will not be subjected to dangerous pressure conditions.

The important feature of this invention is the arrangement of the apparatus whereby `when substantially all of the solid carbon dioxide in the converter tank l is used up, the tank maybe quickly re-charged and brought back to operating conditions.

To re-chargethe tank 1, valves 13 and 18 are closed. The pressure in tank 1 may then be dropped to operating pressure by opening the blow-oli valve 15 at which time any sediment, moisture or dirt which is collected in the tank is blown off. Closure 2 is then removed and the tank recharged with pieces of solid carbondioxide. The closure is thensecured in place. With this apparatus instead of waiting for the pressure in the tank to build up by sublimation, it is only necessary to open valve 18, and if valve 17 is open, the gas pressure in tank 1 may be built up to the operating conditions very rapidly. It should also be noted that with this arrangement the carbonating apparatus can be used even during the re-charging of tank 1 since carbon dioxide may be delivered from tank 14 to the carbonator, through pipes 16 and 2.. Also, even Vif tank 14 is empty, if desired, carbonating can continue by supplying gas from the gas holder through pipes 23 and 21 although no cooling action with the cooling coil 28 can take place.

Attention is called to the fact that the lower f or one of the lower turns of the condenser coils 8 may be provided with one or more small holes as indicated at 40 so that if there is any liquid carbon dioxide in the bottom of tank 1, it may be blown out into the receiver 14 before recharging the tank 1. These holes 40 are placed in the condenser coil sufficiently above the bottorn of tank 1 so that no moisture, dirt or sediment will blow through the connections into the receiver.

Temperature conditions may arise in the use dioxide has sublimated or even when the liquid in the receiver has entirely changed in the gas,- eous form at which time the carbon dioxide may still be under considerable vapor pressure. It is of the converter when most of the solid carbon necessary in this case to create lower temperacarbon dioxide flows through coil 35, expander valve 27' and line 39 into the casing 34 and in intimate .contact with coil 35. At this point it should be noted that two different operations may occur because of the presence of the two expander valves 27 and 38. In the rst operation it will be assumed that expander valve 38 is fully open so as to have no action and expander 27' is adjusted to eiect a reduction in pressure of the gas passing therethrough. Some of this cooled gas flows through the cooling coil 28 while some of it ows around through pipe 39 as above stated into the casing 3i. The gas escaping through the expander valve 27 is cooled by the well-known Thomson-Joule effect which effect is well-known to be much greater for carbon dioxide than for many other gases. The colder gas circulating around the coil 35 ei'ects'l the reliquefaction of the carbon dioxide gas passing therethrough. The gas in chamber 34 escapes through `line 36 into line 23 for use in carbonating if valve 24 is closed, or into the gas -holder if it is open.

Under the conditions just stated, the cold carbon dioxide passing through expander valve 27 is delivered in part to the cooling coil 28 and in part to the casing 3i. The apparatus may alsol be operated with expander valve 27 fully open and expander Valve 38 adjusted to effect a reduction in pressure. In this case a part of the gas going through the line 26 is by-passed into line 39 and expanded through the valve 38 to produce cold gas for reliquefaction of the gas passing through the cooling coil 35. Of course, in both cases after the apparatus is working so that the gas is being condensed in coil 35, liquid carbon dioxide will be passing through the expander valves 27 or 38, depending upon which one is operating.4 In the second case however, with valve 27' open, the gas and/or liquid carbon dioxide coming from the coil 35 goes directly to the cooling coil 28 and only a portion of it is by-passed through the valve 38. It may be that only a part of the gas passing through the cooling coil 35 is liquefied depending upon the temperature and pressure conditions existing in the system. This does .not however interfere with the operation oi the apparatus.

From the foregoing disclosure it will be apparent that this invention resides in certain. principles of construction and operation which strictly limited by the disclosure, either in the drawing or specifications, as given for the purpose of illustrating my invention, but rather to the scope of the appended claims.

What I seek to secure by United States Letters receiver connected to one end of the condenser coil.

2. A carbon dioxide converter as described comprising a tank to be charged with solid carbon dioxide, a closure means for sealing the tank, a condenser coil `supported within said tank, the intake end being open at full bore to the interior thereof and the outlet end extending exteriorly thereof and means for blowing down the pressure in said tank.

3. A carbon dioxide converter as described comprising a tank to be charged with solid carbon dioxide, a closure -means for sealing the tank, a condenser coil supported within said tank and open to the interior thereof, a liquid receiver connected to said coil and a connection between the liquid receiver and the top of said tank.

4. In a converter of the type described the combination comprising a closed tank into which solid carbon dioxide is to be charged, a liquid receiver, a condenser within said tank and conneclions between the condenser and the liquid receiver.

5. In a converter of the type described the combination comprising a closed tank into which solid carbon dioxide is to be charged, a liquid receiver, a condenser within said tank and a pipe connection extending from near the bottom of the liquid receiver to the top of said tank and having the control valve therein by means of which gaseous carbon dioxide may be delivered from the receiver to the tank.

6. In a combination as described, a tank, means for hermetically sealing the tank, a condenser coil within said tank and open to the interior thereof, a liquid receiver connected to said condenser, 'a carbonator and a connection between the liquid receiver and the carbonator.

'7. In a combination as described, a tank, means for hermetically sealing the tank, a condenser coil within said tank and open to the interior thereof, a liquid receiver connected to said condenser, a carbonator and a pressure reducing valve in the connection between the liquid receiver and the carbonator.

8. In a refrigerating and carbonating apparatus the combination comprising a sealable tank to receive solid carbon dioxide, a condenser coil in said tank open to the interior thereof, a liquid receiver connected to said condenser coil, a carbonator, means connecting the liquid receiver to the carbonator for delivering gaseous carbon dioxide from the receiver to the carbonator, a cooling coil in said carbonator and a connection be.

tween the cooling coil and the liquid receiver.

9. In a refrigerating and carbonating apparatus the combination comprising a sealable tank to receive solid carbon dioxide, a condenser coil in said tank open to the interior thereof, a liquid receiver connected to said condenser coil, a carbonator, means connecting the liquid receiver to the carbonator for delivering gaseous carbon dioxide from the receiver to the carbonator, a cooling coil in said carbonator, a gas holder and a connection between the cooling coil and the gas holder.

10. In an apparatus as described, the combination comprising a solid carbon dioxide tank, means for sealing said tank, a condenser coil in said tank open to the interior thereof, a liquid receiver connected to said condenser coil, a pipe connection between the liquid receiver and said tank, a carbonator and a connection between the liquid receiver and the carbonator including a pressure reducing valve.

11` In an apparatus as described, the combination comprising a solid carbon dioxide tank, means for sealing said tank, a condenser coil in said tank open to the interior thereof, a liquid receiver connected to said condenser coil, a pipe connection between the liquid receiver and said tank, a, carbonator and a connection between the liquid receiver and the carbonator including a pressure reducing valve, a cooling coil in said carbonator and a connection between the liquid receiver and the cooling coil including a pressure reducing valve.

12. In an apparatus as described, the combination comprising a solid carbon dioxide tank, means for sealing said tank, a condenser coil in said tank open to theinterior thereof, a liquid receiver connected to said condenser coil, a pipe connection between the liquid receiver and said tank, a carbonator and a connection between the liquid receiver and the carbonator including a pressure reducing valve, a cooling coil in said carbonator, a connection between the liquid receiver and the cooling coil including a pressure reducing valve and a gas receiver connected to said cooling coil.

13. In an apparatus of the type described, the combination with a cooling coil and a source of carbon dioxide connected thereto, of a heat exchanger in the connection including a coil directly connected therein and a casing surrounding the coil, and a connection between the casing and the two cooling coils including an expander valve.

14. In an apparatus of the type described, the combination with a cooling coil and a source of carbon dioxide connected thereto, of a heat exchanger in said connection including a second cooling coil connected directly in said connection, a casing enclosing the second cooling coil, a pipe connection between the casing and the two cooling coils and an expander valve in said connection.

15. The method of employing gaseous carbon dioxide for refrigerating purposes comprising the steps of expanding a stream of carbon dioxide to reduce its temperature and pressure employing a portion of the expanded stream for cooling purposes and employing another portion of the expanded stream for cooling the entire stream before expansion to liquefy it.

16. In an apparatus as described, the combination comprising a tank source of carbon dioxide, a cooling coil connected to said tank, a pressure reducing valve tween the coil and the tank, a second cooling coil connected to the rst cooling coil, an expansion valve in said connection, a casing surrounding the rst cooling coil, a pipe connection between the casing and the low pressure side of the j expansion valve and a discharge connection to said casing.

17.' In an apparatus as described, tlle combination comprising a tank source of carbon dioxide,

a cooling coil connected to said tank, a pressure reducing valve in the connection between the coil and the tank, a second, cooling coil connected to the rst cooling coil, an expansion valve in said connection, a casing surrounding the rst cooling coil, a pipe connection between the casing and the low pressure side of the expansion valve, having an expansion valve therein and a discharge connection to said casing.

JUS'I'US C. GOOSMANN.

in the -connection 'be- 

